Paper machinery



Feb. 28, 1961 w. A. WHITE, JR 2,973,034

' PAPER MACHINERY Filed March s, 1958 2 Sheets-Sheet 1 AIR SUPPLY 35 LIQUID LEVEL /0 CONTROL FIG-2 4o INVENTOR.

L WILLIAM A.WH|TE,JR.

ATTOR N EYS Feb. 28, 1961 w. A. WHITE, JR 2,973,034

PAPER MACHINERY Filed March 5, 1958 2 Sheets-Sheet 2 INVENTOR.

WILLIAM A.WH|TE, JR.

ATTORNEYS PAPER MACHINERY William A. White, Jr., Water-town, Ohio, assignor to The Black-Clawson Company, Hamilton, Ohio, 2! corpora tion of Ohio Filed Mar. 3, 1958, Ser. No. 718,736

9 Claims. (Cl. 162-339) This invention relates to paper making machines.

The invention has particular relation to the control of the flow of stock through the headbox of a relatively high-speed paper machine, and it is especially applicable to headboxes of the air loaded type wherein a cushion of air at a desired pressure is maintained in the upper portion of a closed headbox. It is a conventional practice to employ one or more perforated rectifier rolls in the path of fiow of stock between the inlet and outlet of a headbox, and special provisions are commonly made to cause all the stock to flow through at least one such rectifier roll. Each perforated roll therefore provides a restriction to the free flow of stock through the headbox, but the restriction offered by each such roll is determined by the pattern of perforations therein, which in turn establish the percentage of open area therethrough, and this value remains constant under normal operation.

'It is a primary object of the present invention to provide a stock supply system for a paper making machine wh ch includes one or more rectifier rolls located in the path of flow of the stock through the headbox and in which it is possible to vary the restricting action of any desired rectifier roll or rolls above the minimum estab lished by the open area thereof.

it is more specifically an object of this invention to vide a stock supply system having the characteristics outlined above in which a hydraulic restricting action of variable magnitude can be created within one or more rectifier rolls in the headbox in such manner as to produce corresponding variation of the restriction olfered by such roll or rolls to the free flow of stock through the headbox.

Another object of the invention is to provide a stock supply system for a paper making machine as outlined above wherein the hydraulic restriction within one or more rectifier rolls is created by the introduction of a secondary flow of stock directly to the interior of such roll or rolls at a pressure such that the secondary stock fiow mixes within the roll or rolls with the main stock flow and is discharged therewith from the interior of such roll or rolls for delivery to the forming member of the paper machine.

it is also an object of the invention to provide for the control of the stock flow through the headbox of a paper machine by means of one or more perforated rectifier rolls each of which includes therewithin a perforate tube having a direct connection to a secondary supply of stock at a pressure such that the secondary stock flow is discharged through the perforations of each such tube into the interior of the surrounding rectifier roll for mixture and outward flow with the main stock flow.

Additional objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings Fig. 1 is a somewhat diagrammatic view generally in side elevation and with parts broken away showing a headbox and associated stock supply system in accordance with the invention;

Fig. 2 is an enlarged detail view in section through one of the rectifier rolls in the headbox of Fig. l as indicated by the line 22 of Fig. 1;

Fig. 3 is a view similar to Fig. 2 showing an alternative arrangement in which the secondary stock flow is delivered to only one end of the rectifier roll rather than to both ends as in Fig. 2;

Fig. 4 is a diagram further explaining the operation of the invention;

Figs. 5 and 6 are views similar to Figs. 2 and 3 showing other mounting arrangements for the rectifier rolls in the headbox of Fig. 1;

Fig. 7 is a diagrammatic view in side elevation illustrating the application of the invention to an open headbox; and

Fig. 8 is a view similar to Fig. 7 showing the application of the invention to a closed pressure type headbox.

Referring to the drawings, which illustrate preferred embodiments of the invention, Fig. 1 shows a fragment of a Fourdrinier paper making machine including a form'- ing wire 1% traveling over a breast roll 11. The headbox designated generally as 13 includes a bottom wall 15, a front Wall 16, side walls 17 and 18, and a combined top and back wall 20 which cooperates with the other walls to enclose the interior of the headbox. The main inlet to the interior of the headbox includes a chamber 22 from which the stock flows upwardly through the passage 23 to the level of the bottom wall 15, and the slice outlet 25 is at the opposite end of the headbox from the inlet.

A plurality of perforate rectifier rolls are provided within the headbox, one of these rolls 30 being shown as located within the inlet passage 23. Three rolls 31, 32, and 33 are mounted generally intermediate the inlet and outlet of the box, and these rolls are shown with their axes in vertically and horizontally spaced relation such that they lie generally in a common inclined plane which forms with the bottom wall 15 an acute angle facing the front wall 16. The mounting of these rolls, howeevr, is such that the surface of each roll is in close relation with the next higher roll such that the three rolls together will intercept substantially all stock flow below the level of the uppermost roll 33. An additional pair of rectifier rolls 3-:- and 35 is shown as mounted adjacent the slice outlet 25.

The main stock supply system for the headbox 13 includes a pump 40 having its intake side connected at 41 to an appropriate source of stock. A conduit 42 leads from the discharge side of pump 4i) to the inlet chamber 22, and is shown as connected therewith by a plurality of branch connections 43 spaced across the width of the headbox. The output of the pump as is shown diagram: matically as regulated by a control 44 adapted to maintain the preset liquid level within the headbox, and the headbox is also shown as provided with a controlled source 45 of presusre air for maintaining an air cushion under predetermined pressure in the top of the headbox. For example, the controls 44 and 45 may be of the type shown in Goumeniouk Patent No. 2,677,991 issued May 11, 1954.

Provision is also made in accordance with the invention for supplying a secondary stock flow directly to the interior of one or more of the rectifier rolls within the headbox, and this may conveniently be done by intercepting a portion of the main stock flow and connecting it through a by-pass line to a secondary inlet to the headbox at the proper pressure. Referring to Fig. 1, a branch line 4h leads from the conduit 42 to the inlet side of an auxiliary pump 5i), and the discharge side of the pump St is connected by lines 51 and 52 to the interior of each of the rectifier rolls 31-33. A throttling valve 55 provides control over the output of the pump 50 as desired, and it is also possible to omit the pump 50 and to connect the by-pass line 49 directly to the lines 51 and 52.

Fig. 2 illustrates in detail one arrangement in accordance with the invention for making the secondary inlet connections between the lines 51 and 52 and one of the rolls 3133, shown as the roll 33. A hollow tube 60 forms the mounting shaft for roll 33 and extends concentrically therethrough, and pressure seals 61 and a driving means, such as a sprocket 62, for tube 60 are also shown in Fig. 2. The tube 66 is perforated at 65 substantially throughout its length within the surrounding roll 33, and in order to provide for substantially uniform pressure delivery of the secondary flow of stock through these perforations 65 over the entire length of the tube 60, both ends thereof are connected to the discharge side of the pump 50, by means of suitable rotary joints 66 connected with the lines 51 and 52. Fig. 2 also shows these connections as provided with control valves 67 for the individual roll, which are shown diagrammatically as of manually controlled type but which can also be of conventional automatic types.

Fig. 3 shows an alternative to the arrangement of Fig. 2 in which the roll 70 corresponds to any one of the rolls 31-33, and it is mounted on a shaft 71 which is solid at one end 72 but hollow from its other end throughout the entire portion of its length which lies within the roll 70. The open end of the shaft 71 is connected at 75 to the line 51 from the discharge side of the pump 50, and the hollow portion of the shaft 71 is tapered to provide a constantly decreasing section in the direction of its closed end for the purpose of maintaining substantially constant pressure discharge therefrom throughout its length. The valve 77 between tube 71 and the line 51 corresponds to the valves 67 in Fig. 2.

The operation of the invention is further explained diagrammatically in Fig. 4, in which the roll R represents the plurality of rolls 31-33 as well as any other selected number of rolls employed in the location of the rolls 31-33 in Fig. l. The main stock flow is maintained at a level 80 which in combination with the pressure of the air cushion in the top of the headbox provides a supply pressure P The liquid level 80 is preferably just sufficient to submerge the roll R, and the restricting action of the roll causes a drop in liquid level to the level 81 on the discharge side of the roll R, and also causes a drop in the discharge pressure to a pressure P The difference between the pressures P and P is approximately proportional to the dilference between the liquid levels 8ft and 81 as shown.

The conditions just described continue so long as the restricting action of the roll R is limited to its physical characteristics, but the present invention provides for controlled increase in the overall restricting action of the roll R by the introduction of the secondary stock flow to the interior of the roll to effect hydraulic restriction to the free flow therethrough which is in addition to the mechanical action of the roll. This result is obtained by supplying the secondary stock flow at a maintained pressure P which is sufliciently less than the pressure P to allow the secondary stock flow to discharge into the interior of the roll R for mixture with the main stock flow without affecting the liquid level 80, and particularly without tending to squirt upstream into the main flow or above the level 80. At the same time, the pressure P should be sutliciently greater than the discharge pressure P for the secondary stock flow to join with the main flow in its passage to the outlet 25 without undesirable turbulence.

It is not essential to the invention that both the roll and the perforate tube therewithin be mounted for rotation Within the headbox. Thus Fig. shows an arrangement otherwise similar to that described in connection with Fig. 3 in which the perforate roll is fixedly mounted within headbox by means such as bolts 91 securing its opposite ends to the headbox walls 17 and 18. In this an'angement, the mounting of the tapered perforate tube 92 is similar to that of the tube 71 in Fig. 3, and its drive sprocket 93 may be mounted at either end butis shown at the inlet end of the tube with the closed end of the tube being supported in a bracket 95 on the outer wall of the headbox.

Fig. 6 shows essentially the reverse arrangement from that of Fig. 5 in that the roll is mounted for rotation and the perforate tube 101 is stationary. The drive sprocket 102 may be located on either end of the roll 100, and rotary seals 193 and 104 of suitable conventional construction are provided between the tubular end shafts of the roll and both the walls of the head box and the tube 101. Otherwise the operation in this form is effectively identical with that of the other forms already described.

The invention is not limited to any particular number of rectifier rolls nor to rolls located in any particular position in the headbox. Thus as stated, the roll R in Fig. 4 represents any single roll or group of rolls in Fig. 1, and the connections shown in Figs. 1-3, 5 and 6 may be applied to any one or more of the rolls 30-35 in Fig. 1. In addition, the restricting actions of the several rolls may be varied with respect to each other, as by suitable adjustments of the valves 67 or 77 for the individual rolls to vary the volumetric flow to each roll. The invention accordingly provides a simple and effective means for obtaining wide variation in the restricting action of rectifier rolls in many different arrangements and groupings in a headbox.

The invention is equally applicable to the modification of existing headboxes as well as to new headboxes, and it is not limited to use in closed headboxes of the air loaded type. Thus Fig. 7 illustrates an open headbox which is shown as generally of the construction disclosed in Corbin et a1. Patent No. 2,747,471 issued to the same assignee as this application and incorporating rectifier rolls 111 and 112. Both of these rolls are shown as connected with a supply pipe designated 52 which corresponds to the same part in Fig. 1. Similarly Fig. 8 shows a closed headbox of the pressure type incorporating four rectifier rolls 121124. Two of these rolls 122 and 123 are shown as connected to a supply pipe 52, and it will be understood that the arrangement of these connections and the respective rolls may be changed in accordance with the principles discussed hereinabove.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a perforate rectifier roll extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means defining a secondary stock inlet directly to the interior of said roll from outside said headbox, and means for delivering a secondary fiow of stock to said secondary inlet at a maintained pressure sufiiciently lower than said first pressure for radially outward flow with said main flow from within said roll to said outlet while providing hydraulic restriction to the passage of said main flow through said roll.

2,, A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, means for maintaining a substantially constant level for said main stock flow within headbox, a perforate rectifier roll extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means defining a secondary stock inlet directly to the interior of said roll from outside said headbox, and means for delivering a secondary flow of stock to said secondary inlet at a maintained pressure sufiiciently lower than said first pressurefor radially outward flow with said main flow from Within said roll to said outlet While providing hydraulic restriction to the passage of said main flow through said roll.

3. A stock supply system for the formizr member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a perforate rectifier roll extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, :1 tube having a perforate Wall located concentrically Within said roll, and means for delivering a secondary flow of stock directly to the interior of said tube from outside said headbox at a maintained pressure sufficiently lower than said first pressure for discharge within said roll and radially outward llow therefrom with said main how to said outlet while providing hydraulic restriction to passage of said main flow through said roll.

4. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, perforate cylindrical rectifying means extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means for maintaining said main stool: flow in said headbox at a substantially constant level just sufiicient to submerge said rectifier means, and means for delivering directly to the interior of said rectifying means from outside said headbox a secondary flow of stock at a maintained pressure sufficiently lower than said first pressure for radially outward flow With said main flow from Within said rectifying means to said outlet while providing hydraulic restriction to the passage of said main flow through said rectifying means. I

5. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a plurality of perforate rectifier rolls extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means supporting said rolls with the axes thereof in vertically spaced relation and with the surface of each said roll in close relation with the next higher said roll providing for interception by said plurality of rolls of substantially all stock flow below the level of the uppermost said roll, means for maintaining said main stock flow through said headbox at a substantially constant level just suflicient to submerge said uppermost roll, a tube having a perforate wall located concentrically within at least one of said rolls, and means for delivering a secondary flow of stock directly to the interior of said tube at a maintained pressure sufliciently lower than said first pressure for discharge within the surrounding said roll d and radially outward flow from within said surrounding roll to said outlet with said main flow while providing hydraulic restriction to the passage of said main flow through said rolls.

6. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a plurality of perforate rectifier rolls extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means supporting said rolls with the axes thereof in vertically spaced relation and with the surface of each said roll in close relation with the next higher said roll providing for interception by said plurality of rolls of substantially all stock flow below the level of the uppermost said roll, means for maintaining said main stock flow through said headbox at a substantialy constant level just suflicient to submerge said uppermost roll, a tube having a perforate wall located concentrically within each of said rolls, and means for delivering a secondary flow of stock direct to the interior of each of said tubes at a maintained pressure sufficiently lower than said first pressure for discharge within the surrounding said roll and radially outward flow from within said surrounding roll to said outlet with said main flow while providing hydraulic restriction to the passage of said main flow through said rolls.

7. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a plurality of perforate rectifier rolls extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means supporting said rolls with the axes thereof in vertically spaced relation and with the surface of each said roll in close relation with the next higher said roll providing for interception by said plurality of rolls of substantially all stock flow below the level of the uppermost said roll, means for maintaining said main stock flow through said headbox at a substantially constant level just suiiicient to submerge said uppermost roll, a tube having a perforate wall located concentrically within each of said rolls, means for delivering a secondary flow of stock direct to the interior of each of said tubes at a maintained pressure sufficiently lower than said first pressure for discharge within the surrounding said roll and radially outward flow from within said surrounding roll to said outlet with said main flow While poviding hydraulic restriction to the passage of said main flow through said rolls, and separate adjustable means associated with each of said rolls for varying the volumetric rate of said secondary flow to each said roll to establish relatively different restricting actions for each said roll.

8. A stock supply system for the forming member of a paper making machine comprising, a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a perforate rectifier roll extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, means defining a secondary stock inlet directly to the interior of said roll from outside said headbox, by-pass means for intercepting a minor portion of said main stock flow at a location upstream from said main inlet and delivering the resulting secondary flow to said secondary inlet, and said by-pass means including means for maintaining said secondary stock flow at a pressure sufficiently lower than said first pressure to effect radially outward flow of said secondary flow with said main flow from within said roll to said outlet while providing hydraulic restriction to the passage of said main flow through said roll.

9. A stock supply system for the forming member of a paper making machine, comprising a headbox having a main stock inlet at one end thereof and a slice outlet at the other end thereof for discharge to said forming member, means providing a main flow of stock to said inlet at a maintained predetermined first pressure, a perforate rectifier roll extending across said headbox substantially perpendicularly to the path of said main stock flow from said inlet to said outlet, a tube having a perforate Wall located concentrically within said roll, bypass means for intercepting a minor portion of said main stock flow at a location upstream from said main inlet and delivering the resulting secondary flow of stock directly to the interior of said tube from outside said headbox, and said by-pass means including means for maintaining said secondary stock flow at a pressure sufliciently lower than said first pressure to effect discharge of said secondary flow within said roll for radially outward flow therefrom with said main flow to said outlet while providing hydraulic restriction to the passage of said main flow through said roll.

References Cited in the file of this patent UNITED STATES PATENTS 1,841,693 Aldrich et a1. Jan. 19,, 1932 2,736,246 Grittenden et al. Feb. 28, 1956 2,736,247 Hornbostel Feb. 28, 1956 2,737,857 Lee Mar. 13, 1956 2,847,913 -Cirrito Aug. 19, 1958 2,892,499 Logan et a1. June 30, 1959 

